add encodeData() to SkImageEncoder, and add encoding to SkImage

src/images/SkImageEncoder.cpp

 
 /*
  * Copyright 2009 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkImageEncoder.h"
@@ skipping 20 matching lines @@
                                 int quality) {
     SkAutoTDelete<SkImageEncoder> enc(SkImageEncoder::Create(t));
     return enc.get() && enc.get()->encodeFile(file, bm, quality);
 }
 
 bool SkImageEncoder::EncodeStream(SkWStream* stream, const SkBitmap& bm, Type t,
                                 int quality) {
     SkAutoTDelete<SkImageEncoder> enc(SkImageEncoder::Create(t));
     return enc.get() && enc.get()->encodeStream(stream, bm, quality);
 }
+
+SkData* SkImageEncoder::encodeData(const SkBitmap& bm, int quality) {
+    SkDynamicMemoryWStream stream;
+    quality = SkMin32(100, SkMax32(0, quality));
+    if (this->onEncode(&stream, bm, quality)) {
+        return stream.copyToData();
+    }
+    return NULL;
+}
+